<template>
<div>
	<router-link tag="div" to="/" class="header-abs" v-show="showAbs">
		<div class="iconfont header-abs-back">&#xe624;</div>
	</router-link>
	<div class="header-fixed" v-show="!showAbs" :style="opacityStyle">
		景点详情
		<router-link to="/">
			<div class="iconfont header-fixed-back">&#xe624;</div>
		</router-link>
	</div>
</div>	
</template>

<script>
export default {
	name: 'DetailHeader',
	data () {
		return {
			showAbs: true,
			opacityStyle: {
				opacity: 0
			}
		}
	},
	methods: {
		handleScroll () {
			const top = document.documentElement.scrollTop||document.body.scrollTop||window.pageYOffset
			if (top>60){
				this.showAbs = false
				let opacity = top/140
				opacity = opacity>1?1:opacity
				this.opacityStyle = {
					opacity: opacity
				}
			}
			else{
				this.showAbs = true
			}			
		}
	},
	mounted () {
		window.addEventListener('scroll',this.handleScroll)
	},
	destroyed () {
		window.removeEventListener('scroll',this.handleScroll)
	}
}
</script>

<style lang="stylus" scoped>
@import '../../../assets/styles/varibles.styl'
.header-abs
	position: absolute
	left: .2rem
	top: .2rem
	width: .8rem
	height: .8rem
	line-height: .8rem
	border-radius: .4rem
	background: rgba(0,0,0,.8)
	text-align: center
	.header-abs-back
		color: #fff
		font-size: .4rem	
.header-fixed
	position: fixed
	top: 0
	right: 0
	left:0
	overflow: hidden
	height: $headerHeight
	line-height: $headerHeight
	text-align: center
	color: #fff
	background: $bgColor
	font-size: .4rem
	.header-fixed-back
		position: absolute
		top: 0
		left: 0
		width: .64rem
		text-align:center
		font-size: .4rem
		color: #fff
</style>